Why DNA Testing Failed to Link the In Cold Blood Killers to a Gruesome Murder in Florida

The cover of Truman Capote’s In Cold Blood.

At the end of 2012, the worlds of classic literature, true crime, and science merged for one thrilling moment. In December authorities in Sarasota County, Fla., announced they would ask to exhume the bodies of Perry Smith and Richard Hickock, convicted murderers whose exploits were the subject of Truman Capote’s “nonfiction novel” In Cold Blood, to see if DNA testing could link the two men to the December 1959 murder of Cliff Walker and his family. On Tuesday the Associated Press reported that, no, it couldn’t:

Authorities said they were unable to match the DNA because only partial profiles could be taken from the exhumed bodies in December, and the Walker crime scene samples were old and degraded. No more tests were scheduled.

“The complication lies in the fact that there’s still some uncertainty,” [Sarasota County Sheriff’s Office Capt. Jeff] Bell said. “It wouldn’t exclude them but it also does not provide us with any level of confidence to say there’s a match because there’s not.”

Thanks for nothing, science! This unsatisfying conclusion helps advance what has become a recurring theme for this blog (and, to judge from the readership levels of the relevant articles, a ragingly unpopular one): the fallibility of forensic science. In films and on television, crime labs are sterile and well-equipped, technicians are brilliant, DNA samples are in perfect condition, and results are conclusive.

Real life is different. As William C. Thompson puts it in an article for GeneWatch, although they are generally reliable, “DNA tests are not now and have never been infallible. Errors in DNA testing occur regularly. DNA evidence has caused false incriminations and false convictions, and will continue to do so.” Labs are underfunded, technicians are overworked. Samples are imperfect. Answers can be elusive—even in cases of more recent vintage than the Walker murders.

Knowing all that, there was no reason to expect that the In Cold Blood exhumations were likely to solve this very cold case. The Walkers were killed in 1959, in an era when DNA testing did not exist, and authorities at the time would’ve had no reason to maintain Christine Walker’s semen-stained underwear in perfect condition just in case DNA testing was ever invented. Even if they had, it can be hard to extract viable samples from a 50-year-old corpse, because corpses decay. The authorities were only able to construct a partial DNA profile from Hickock’s and Smith’s bodies, which basically means that, even if all else went well, technicians would only have been able to place Hickock and Smith within a larger group of people who also matched the sample.

Still, it’s a shame that the DNA test was inconclusive, because “Smith and Hickock did it” wasn’t a terrible theory. The long-unsolved Walker murders bore surface similarities to the murders of the Clutters, a Kansas farm family whom Smith and Hickock killed in November 1959. What’s more, the two men were known to have been in Florida at the time the Walkers were killed; when they were apprehended in late December 1959, Hickock was carrying a knife that resembled one that had been stolen from Cliff Walker.

Circumstantial evidence? Sure. But circumstantial evidence is better than no evidence, which is probably why Sarasota authorities told the AP they’re not abandoning the In Cold Blood angle, inconclusive DNA results be damned. “The mystery continues and we’ll look for other opportunities,” Capt. Bell told the wire service. “We’ve reached a point where we don’t believe we’re going to accomplish that through DNA testing.” At least that’s one thing they know for sure.

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